<!-- index.html -->
<!DOCTYPE html>
<html>
<head>
    <style>
  .big-font {
    font-size: 50px; /* 设置字体大小为24像素 */
  }

    </style>
</head>
<body>
<p class="big-font" id="info">Hello HarmonyOS！</p>
<script>
    function htmlTest() {
        document.getElementById("info").innerHTML = "Hello World!";
    }
</script>
</body>
</html>